To meet the demands and opportunity of our modern society, sleep curtailment is common among many Americans. Women now occupy a more prominent place in the work force without reducing most of the responsibilities at home. Many women struggle to balance family and work demands. Consequently, sleep needs are often pushed to the bottom of women's daily priority list. Prior research has indicated that short sleep duration is associated with higher levels of pro-inflammatory serum cytokines, which are associated with postpartum depression. However, few research studies have directly examined the relationship between sleep duration during pregnancy and postpartum depression. The proposed study aims to address the gaps in our knowledge and understanding of sleep duration during pregnancy and its effects on preterm delivery and postpartum depression. We hypothesize that shorter sleep duration during pregnancy increases the risk of spontaneous preterm delivery and postpartum depression. We further hypothesize that systematic inflammation is the causal mechanism in the association. Repeated measures of sleep duration during pregnancy will be obtained in a longitudinal cohort study design. Socio-demographic information and prior medical and obstetrical history will be collected through survey questionnaires and medical record abstraction. Repeated samples of pro-inflammatory cytokines levels from blood serum will also be ascertained. Findings from the proposed study are likely to have significant implications in facilitating the management and prevention of spontaneous preterm delivery and postpartum depression. My long-term research goal is to obtain training in sleep medicine research and combine it with my background in biostatistics and epidemiology to become a productive, independent maternal and fetal medicine researcher with a focus on sleep medicine. My mentors and I have developed a comprehensive and structured training plan that includes coursework, seminars and conferences, and mentored independent research projects. My prior training in Epidemiology, Biostatistics, maternal and child health place me in the right position to further my training in sleep medicine and to investigate the role sleep duration during pregnancy plays in adverse maternal and fetal outcomes. PUBLIC HEALTH RELEVANCE: Findings from the proposed study will enhance our understanding of sleep duration during pregnancy and its effects on spontaneous preterm delivery and postpartum depression. As it is widely documented that postpartum depression adversely affects maternal-child relationships and child development, the identification of sleep as a target of interventions in pregnancy would have substantial importance from a public health standpoint.